Maybe you should go to a shelter! Just say you're looking for a "volunteer age" and your parents would think it's good for growth. Then just casually ask to go look and see if you find a cute cat! (Seniors are a great option that is what my mom fell for) Then have a worker set up something to meet. All summer long I made my mom go to shelters with me and we ended up adopting. And if they had a pet, remind them of that! Cats are the best addition to the family. If they think cats are bad for pooping, ask for a dog, then say this: dogs poop, smell bad, shed, and need to be taken outside to go to the bathroom. It's worth their unconditional love, but cats go in a litter box and you could offer to clean it! Hope this helps!